Where to go now with my IMS

So I have a 2002 C4 with 90k kilometers on it (55k miles). In early 2013 (with 70k kilometers - 45k miles) I needed a new clutch - so had the following done: clutch, flywheel, air oil separator, water pump, and an LN IMS classic retrofit (single row). So I'm now 4.5 yrs later and it appears the recommendation is that at 4 yrs/50k miles I replace the LN IMS bearing or upgrade to 'the solution'. However with so few miles (3k miles per year), it would take me another decade to reach the 50k miles mark. Should I be worried, or am I in at least as good position if I had the original OEM IMS bearing and had never changed it?? Mike

Great question, I'm the new owner of a C4s with the original IMSB. Bought the car knowing I would need to do a clutch soon after and plan to replace the RMS and IMSB at the same time. I will likely drive it more than you but not much. So do I change the IMSB every 5yr regardless of mileage? I'm hesitant to go with the total solution based on lack of installers in my area. Can't wait to hear thoughts on this from folks in the know.

I would imagine the solution and the plain bearing have a similar install process....so if you're doubting your mechanics skills to do the solution right, I'd have the same concerns with the plain bearing. I wish I did the solution. I did the bearing from LNE and even then I am paranoid that it will go anytime.

What do you mean by"plain bearing"? The IMS Solution is a plain, or journal bearing. Is there another plain bearing replacement available?

LNE has a couple different fixes https://lnengineering.com/index.php/products/ims-bearing-retrofit-kits-for-porsche-m96-97-engines.html when I say the "plain bearing" I mean the cheaper fix to the IMS issues and not The Solution that includes the hose, oil filter & adapter.

Quotes source post: 14515905

AWD I wish I had done the solution as well. I was not aware it included the LN oil filter adapter. In addition I had a local indy do the install of a Single Row Pro, and he never sent the warranty information back to LN. It needed to be sent in within 10 days of install. %$#$%#%%% So I have spent the money for an upgrade with 6yr/75k warranty that I cannot make a claim against in the event of a boom.

My LN Pro was completed prior to sale at my request; by my dealer; via an Porsche Indy he respected and trusted that has done this job many times. The LN replacements are not guaranteed unless done by an LN approved shop. So mine is not guaranteed.

"I wish I had done the solution as well. I was not aware it included the LN oil filter adapter." "The Solution" package does include a "spin on filter adapter". This is not the same as the regular "spin on filter adapter" though as it includes the feed for the plain bearing (that rides on a film of oil). The feed is derived from the "clean side" of the filter so the bearing gets freshly filtered oil.

Quotes source post: 14516004

isn't the warranty that they give you the money back for the bearing?

Edit

Thanks for input. When I did the original LN IMS bearing in 2013 this was the only available fix for the problem. There was no pro double bearing nor "the solution". But now I have a car with a retrofit bearing outside the period that LN engineering claims the bearing is designed for. The OEM bearing of course had no serviceable timeframe (although I guess it probably should have). I feel like the whole reason I originally changed it was for 'peace of mind', and now I'm feeling angst about it again!! So again I ask, am I in a safer position with 4.5 yr old LN IMS bearing ? Does anyone have any idea what my risk is ? Am I back to an 8-10% risk I had with the original OEM bearing.

Quotes source post: 14516102

I see that now in the photos. In either case it would have put more $ weight on the decision side to go with the solution, which I think was $1000 more than Single Row Pro. just been kicking myself after the work was done, hine sight is a PIA

Quotes source post: 14516147

I have 9000 miles on mine now, 2 oil changes with new magnetic drain plug and cutting filter and no signs of any debris. Due now for oil change, I just received my first oil sample kit to use from Blackstone. I would suggest frequent oil changes and send oil for analysis each time, that is what my plan is

I would just bite the bullet and install the "Solution" it will hurt a lot less at first then the other (low percentage) option. Plus, if you ever sell it, it should hold it's value with a buyer.

In a very similar situation. Purchased my 03 C4S about a month ago with the IMS Retrofit done at 78k in 2013. The car just hit 100k, so I'm about 20k into the bearing, but 4 years in (the recommended lifespan of the retrofit). A little concerned, but should I be? Worth going out an doing the solution for peace of mind shortly down the road? Admittedly, when I bought the car, I thought LN IMS Retrofit = Peace of mind forever

Quotes source post: 14516102

Correct......the filters are different sizes. Meaning the threaded hole is a different diameter. Ask me how I know

Quotes source post: 14516205

same here. I'll be removing the bearing at 4 years old but t will have less than 20 000km of use on it by then.

Sounds like we need an actuary to determine the risk!! Whats a 2002 C4 worth? 25k at most?? So is putting 2k into it prophylactically worthwhile to stop a 10% event? Yes maybe... But a 5% event? Definitely not. Do 5% of the LN classic retrofit bearings eventually grenade ?? Time will tell, but seems failures are relatively low so far.. So I guess the answer is no one knows. I suppose I'll just wait until I have my clutch done and see what new options are available at that time..

Quotes source post: 14516207

Hmmm... I didn't know ^^that^^ I thought the only difference was the oil feed for the plain bearing - I'll have to check it at the next oil/filter change as I've still got a new Napa Gold 1042 lying around somewhere

Quotes source post: 14516301

I use Wix 51348. The hole dia on the Solution is smaller.

My plan is to change it with every clutch . I installed the retrofit too and not worried about the 4 years , which seems to be the warranty guidelines . More the mileage , 50k miles or 80k kilometres , I'll do both although it could go longer

I can't think of a reason to change the LN bearing based on time. It is run time that determines the life of an anti-friction bearing, so long as the oil is clean.

I have read about the possibility of a discount on the solution if you're replacing a LN retrofit product. ​​​​​​I think the time interval covers LN to some degree but if it's a concern replace it with the solution. I wish I had gone the solution rather than the retrofit. I've got another 3 years according to the service interval so ill have the solution installed then. ​​​​​​

Quotes source post: 14515818

My advice is change it. Apparently the Solution is the best option. My LNE IMSB upgrade lasted about 2 1/2 years, 20K miles.

Wow that sounded ominous. Did your retrofit IMS bearing grenade your engine?? 2.5 yrs and 20k miles is well within the warranty of the product.

It did. The good news is now I have an even better engine. The warranty is only for the cost of the bearing.

Quotes source post: 14517083

That scares the **** out of me.

That whole lne situation with the bearing expiring after x amount of time vs usage is such a load of crap. Just another example of injecting fear into owners to spend more money on wasted time and parts.

Quotes source post: 14517204

Based on your side picture, I would imagine your 996 see's a bit of track time. How much of those 20k miles was spent on the track out of curiosity? Was it a failure on the track or normal conditions? I ask because I thought there was a caveat that the LN products aren't covered under warranty if the car is used on the track.

I do several HPDE days a year (average about 4 per year). Always on street tires and in the B group. The failure was coming home from picking up groceries - 5 mph in 1st gear.

Oh wow thats scary. Was there a post-mortem done?? LN engineering have any explanation? Did they warranty the bearing in some way (I know the cost of bearing is only thing they will cover).

Quotes source post: 14517204

I am guessing you have some folks, me as one of them, now having this thought in the back of our minds. Did you motor go because of the IMS LN Bearing our something else was the cause? Also, which LN bearing did you have?

Quotes source post: 14517434

Maybe I'm off but all the notes I've seen on IMSb failure suggest it's a low RPM issue. Track time is hard on the c-r bolts, chains & oiling system, but it's the low rpm environment that wears down the IMSb relative to high rpm driving. Track failures often involve excess heat & compromised lubrication, while IMSb failures drift towards regular street driving at lower rpms. I've spent a bunch on my 996 since buying in early 2016, so maybe I'm not the best example, but the Solution was the first thing I did after a basic inspection & service. No regrets & 17,000 miles later my car is healthy & puts a smile on my face without IMSb worries. $3500 for the install and I used the labor to knock out some other items that were in need of service like a worn throwout bearing & cracked AOS.

Call LN and ask them. My dealings with them have been great - they're very responsive and will answer your question and that will be that. As far as keeping it vs. changing out for the Solution. How long are you going to keep the car? If you're going to keep it long enough to outrun the mileage service interval for your current bearing, you might as well change it now and have the peace of mind. If not, maybe leave it and let the next owner fret - or change it now and potentially boost the resale a bit.

I come at this from a different perspective. I had Jake install the IMS Solution after purchasing my low mileage 2002 C2. I wanted the issue off the table and spending an additional $1,000 over the cost of the retrofit just made sense to me. I planned to keep the car forever, but came across a few others and ran out of room. From this work and some other preventative maintenance that was done sent a clear message to interested parties when I went to sell it that they could just drive it. It was an easy sale at the top end of the market.

Quotes source post: 14515818

This is common language with many parts / service needs. But I think a bearing is different than many other periodic maintenance because it seems that "time" (4yrs) probably has way less influence on the need to replace than "miles". I don't know how an IMSB would wear simply with time, unless there is some chemical relationship with the ceramic or steel. There are many other parts that are good to replace when the "time" expires: certainly cam belts (on non-996 cars), plug wires, tires, anything rubber or plastic, etc. In other words there are parts that degrade with time in addition to degrading with mileage. The IMSB certainly degrades more with mileage than it does with time, so I wouldn't worry about the time. It is a poor spec anyway, it should read "4 yrs/50k miles, assuming you drive 12.5K miles per year".

Given that the single-row retrofit bearings DO have some number of known failures while the dual-rows do not, I would replace the single-row retrofit bearing with another product. "I in at least as good position if I had the original OEM IMS bearing and had never changed it??" Hard to say. There are isolated reports of retrofit bearings failing even though the original bearing was seemingly in good condition when removed. This is often attributed to using un-blessed installers.

My $0.02 I believe the time limit on these bearings was set as a safeguard until more data was collected on wear and failure. The only time related 'wear' on these types of bearings could be chemical attack from combustion products in the engine oil. As these bearings are open and not sealed with grease. The ceramic ***** are immune from this, but the steel race is not. For most people who realize that frequent oil changes (5-7k) on these m96 motors is a good safeguard, the amount of combustion products that build up between oil changes is much less. So I wouldn't sweat it personally...

Quotes source post: 14517954

^^I think this is misleading & not aligned with the experience of those on the forum. The bearings wear down over time assuming some degree of use (99.9% of engines). They're a wear part. See the thousands of 9x6 motors that have asploded. Any producer will have some degree of buffer in their product warranty vs. the actual, expected product lifespan. The existence of a change interval on most IMS products reflects the fundamental change in how the aftermarket treats the IMSb lifespan (wear part) relative to Porsche at the time of production (permanent bearing for the engine).

Quotes source post: 14517706

I've been "looking" for a 996 or 997 for a few months. I planned on buying next March. Two weeks ago I saw an ad for a low mileage 2002 996 with the IMS Solution and Fabspeed exhaust installed and jumped at it. Two days later it was parked in my garage. IMS Solution will definitely help you sell your 996!

Quotes source post: 14518004

Not sure what you are saying, you are stating that if I buy a LNE bearing and drop it in some oil with a few thousand miles on it in a coffee cup, after 3 years I'll pull it out and it will be worn?

Quotes source post: 14517954

I wish we could get a definitive answer from LN about this. My bearing isn't due for replacement until 2020, but it will be at less than half the mile limit on it by then (at most). It seems kind of a waste to replace a bearing at half its wear life.

Quotes source post: 14518251

I'm trying to say it's impractical to use hypotheticals that don't have much relevance IRL. I get your point about the chemical side of things & don't have a coherent position to debate that. So maybe I'll just shaddup.

Quotes source post: 14517812

If you look at the bearing only retrofit, it replaces a single row bearing with a new dual row bearing.

Quotes source post: 14518666

I was under the assumption that the new Single Row Pro was the best choice, if not going with the solution, this was confirmed when I was in contact with LNE about my bearing not having a valid warranty. Due to the 10 day window that my indy did not adhere to.

Quotes source post: 14518262

Yes, our intervals are conservative, but I do feel they are fair. All we can go with are the known facts and observational data. The dual row bearing has twice the load capacity and failure rates are 1% versus the single row bearing which was at 8%. Load plays into this greatly. The ceramic hybrid bearings do wear slower than conventional bearings, but yes, they still have steel races and in bearings that have failed (ours included), we have seen corrosive wear and pitting. The environments these bearings live in are quite tough and the majority of cars that fail have very low use and short drives. Acid buildup (increase in the oil's TAN) from combustion byproducts and moisture can cause corrosive wear in other places as well. That's why we say 6 months or 5k miles for oil changes, but on cars that get very short drives or winter use, we say 3 months or 3k miles tops. Add in that these cars in stock form have high amounts of fuel intrusion into the crankcase which doesn't help matters along. For those having to replace their bearing again based on either time or miles, there is a trade-up program in the works, as someone else here mentioned. This will indeed include the IMS Solution and will have a larger rebate associated with it of course.

Quotes source post: 14518813

We're usually flexible on the time frame, but if the original bearing cannot be supplied along with the work order showing that the proper pre-qualification was done, in that case we can't offer a warranty. If you still have the original bearing and paperwork, we can get this straightened out for you.

Quotes source post: 14516075

I wanted to clarify this. You do not have to use an approved shop, however, there are strict requirements that have to be met to qualify for a warranty, including pre-qualification. What you do get with using, for example, and IMS Solution Certified shop is someone that we have trained (though The Knowledge Gruppe) and follows our requirements to the T. I hate to admit it, but there are tons of shops that aren't qualified to even work on a lawnmower. Having Certified Installers are to help weed out shops that we wouldn't want to have work on our own cars or that of friends and family.

Quotes source post: 14516318

The normal spin on oil filter adapter has a 13/16-16 filter thread and uses a Napa 1042 (Wix 51042), whereas the Solution uses a 3/4-16 thread. Both filters are equal size and construction, only difference is the Solution's Napa 1348 (Wix 51348) has an internal bypass to ensure the solution gets oil at cold start first. We exclusively use the Napa Gold, Platinum, or Wix - even recently I cut open about 20+ filters from different companies and the quality of the Napa/Wix are far superior to even the Mann or Mahle equivalents.

Quotes source post: 14519167

I do I will be in contact with you next week. Thank you David

Hi Charles Can you give an approx failure rate for the LN classic single row retrofit (the one I have). Its really hard to know what to do without knowing what the risk is. Is it the same as the OEM single row bearing (~8%). Mike

Quotes source post: 14519172

Thank you for taking the time to clarify some of these questions / concerns.

Quotes source post: 14519185

Verified failures from a defective replacement bearing installed on a properly pre-qualified engine is less than 0.001%. If you take into consideration all claims reported (but not verified or pre-qualified) and non-reported claims collected from posts on forums, that number rises to 0.0046%. Still a fractional value of the factory 8% failure rate. We attribute this to the improvements a ceramic hybrid bearing provides. For the Single Row Pro, Classic Dual, and IMS Solution, failure rate is 0%. For the application, it was calculated that the L10 value for the 6204 bearing (based of size of bearing) is 10% failure within 90,000 miles (assuming average 60 mph in top gear). Complication here is that that's assuming the engine is running at one fixed RPM. Lower engine RPM = higher wear and lower bearing life. That's where depending on environmental conditions, how the car is driven, etc. why the IMS bearing has such a wide range of failures at all kinds of miles and ages. It's almost impossible to predict a failure and when is the right time to change the bearing. Long story short, the lower the rpm, the lower the bearing life. What is interesting is that the 6305 bearing used in the 06-08 models is a much larger diameter (and load capacity matching the dual row bearing) and because of this, the max RPM for the 6305 bearing is perfectly matched the the speed of the IMS, which is 1/2 the engine speed. I still believe the 6305 bearing is a solid part and not a concern as long as early in life you remove the grease seal and then change the oil more frequently.

Thanks for your reply Charles. So this is where it gets really confusing for me. I'm a physician, not a car person. In medicine I use statistics to evaluate disease and treatment. When I apply that to this problem.. well everyones advise just doesn't add up. So lets assume my patient is a "2002 996". I'll call him Gary (the grenade). He has a disease called "having an OEM IMS bearing". I see him in my office and tell him that he has an 8% change of dying while out and about from his heart exploding. He of course is mortified and wants something done. I say, no problem Gary. Theres a new treatment where we can change a part of your heart to a ceramic part. Its just like the original but its a different material. A few people die during the surgery, but if you get it done by a good surgeon it reduces your change of dying to almost 1% (Charles estimates much less than this from above, but I'll be ultra-pessimistic for Gary). Gary is like great, sign me up. So Gary has his surgery. Its a success! Hes loving life with his new ceramic IMS bearing. A few years later he sees a commercial for an even newer treatment. This new treatment replaces the part in Garys heart, and its a complete cure. Gary comes back and says "Doc, I've got a 1% chance of my heart exploding right now. What about this new treatment thats a cure?". How to we determine what to do? So this is a common situation so there are some statistical tools we use to evaluate this. For Gary's original surgery we can determine the NNT (number needed to treat). This is how many people would need to receive the treatment to save one life (or prevent one event). For an 8% to 1% absolute risk reduction, the NNT is 100/(8-1) = ~14. Then economically (I live in Canada so we ignore this part ) we can put a value on this procedure based on its cost. Lets say the procedure costs $1500 dollars. We can multiply 14x1500 = $21000. So it costs $21000 to save one life. Not bad. We of course can't put a dollar value on a human life. But we can on a 996. So to spend $21000 to save one 996 is actually pretty reasonable insurance, provided the value of these cares are about that figure. So lets go to Gary's second problem. Should he have his second surgery to completely cure himself of "IMS bearing". Now its a little bit different. To calculate his NNT his pre-procedure risk is 1% (because he has the ceramic bearing), and the post-procedure is 0% (if he doesn't die during surgery. So NNT = 100 / (1-0). Now his NNT sky rockets to 100. We would have to do surgery on 100 patients to save one. This second procedure is more expensive, lets say $3k. So now the treatment to save one Gary costs 100x3k = $300,000! This procedure is no longer worthwhile unless Gary is worth $300,000. So maybe we really love Gary so we will do it. But Gary's insurance company decided this treatment is not necessary. Sigh. PS The math for 'the cure' of course is much better if Gary never had the original surgery. The NNT is then 100/(8-0) = 12. So the cost to save one Gary becomes 12 x 3k = 36k.

Gary is a stubborn 20 year old that is at the point of being reckless with a handful of personal issues and poor choices, but still manages to hold a somewhat steady job, that is until his girlfriend (Lady IMSB) breaks up with him, where he spirals out of control falling into a pit of depression because his mom always said his girlfriend was nothing but a menace and would break his heart one day. Realistically, Gary should have either never got with his girlfriend to avoid imminent implosion, or he should just trade her in for a better looking, more robust model with less mental issues, leading to a happy fulfilling life. Which Gary do you want to be?

Quotes source post: 14515818

I would say if you need a clutch right now then do the bearing again. Otherwise just drive the car and enjoy it. My 02 C4 had 113K miles on it when I needed a clutch so I replaced the original with an LN. My OEM bearing showed no signs of wear, shaft, seals etc. There was oil in it, but otherwise it was good. When I need a new clutch in 50 or 60K miles I'll probably replace it. When cars that have had an LN installed grenade how is it known that the bearing was the problem? Not saying it is or isn't, but how do we know? There have to be a large amount of 996's with the original bearing and well over a 100K miles on the clock and supposedly the LN bearing is superior so why wouldn't it go 100K?

Gary could also turn into a minivan and have an even lower chance of his heart exploding, but live in shame the rest of his life envying everyone else.

Quotes source post: 14519856

Wow!... That's way too complicated - classic example of "making a mountain out of a mole hill". We're not talking about a $300,000.00 operation here Doc... If you can't/don't want to DIY it, break out your wallet and spend the $4k to have The Solution installed - you'll never have to worry about it (the IMSB) again... Since we're talking internal organs, this doesn't mean that because you've now got a bionic heart, your kidneys won't fail...

The difference, of course, is that as a surgeon, you don't get to cherry-pick your patients and thus ensure mostly-to-only-positive outcomes. I assume that you're willing to help whoever comes along, rather than pre-qualifying them to eliminate the sickest patients... Imagine how frustrated Gary will be when Jarvik announces - again - that their PREVIOUS heart has a previously-undocumented 0.5% chance of failure, but he can upgrade to the new-new-NEW Jarvik 2117 (and even get a rebate if you provide your previous two hearts)... This is a fictitious supposition, not analogous in any way to any person or entity, living or dead, known or unknown, in this or any parallel/alternate existence.

I would hardly say this IMS issue is a mole hill. And the logic of spending 4k on a 25k car to prevent a very small event is strange to me. The $300,000 I quoted is not the cost of an operation, its the cost of preventing one engine grenading from an IMS, after you have already installed a classic LN ceramic retrofit bearing, based on the information Charles provided. If I did the calculation with his << 1 percent risk, the number would be in the millions of dollars. Which is many, many times the value of a single 996. It suggests very marginal returns from upgrading to the solution from a single row LN ceramic bearing, which many in my position are struggling with. and yes 5CHN3LL any conclusion you draw has to be based on accurate information. So that is why I used 1% as a conservative estimate of a ceramic LN retrofit bearing failure rather than the 0.0046 percent. Mike

Quotes source post: 14520050

In your case, you've already replaced the (ball) bearing with another ball bearing that has a predetermined maximum service life. Run it to the maximum/end of service, then determine if you still want to keep the car. If you do, replace the ball bearing with The Solution...done. No amount of hand wringing in the meantime will make any difference. As you say, the chances of your engine grenadeing is small. I think your miscalculation comes in the assumption that it's a "$25k car"... It's actually a $25k engine rolling around in a free chassis !

Quotes source post: 14516147

The IMs Solution was available in 2013. I agreed to product release to the general public which occurred November 11, 2011. Prior to that, only my complete engine purchasers were privy to the IMS Solution, for their builds.... Which was the original intent of the product. When making a consideration of what IMS product to use, only keep in mind the time that you plan to keep the car. If you plan " forever" then the only thing that makes any sense is the Solution. If any lesser amount of time, then make the decision based on cost vs recommended replacement intervals.

Ok great that's great advice. Before this discussion I was missing a few pieces of information a) the approximate failure rate of the LN ceramic retrofit bearing (which I now know is very small, less than 1 percent if your engine was deemed worthy of it) b) that failure rate in bearings is much more related to amount of use (miles driven) than time in service c) that there are many, many ways other than the IMS that this engine can decide to commit Seppuku - so even 'the solution' will not make it eternal Based on all this, my personal approach will be drive the car with this bearing until at least 50k miles or I have a another reason to separate the engine from the vehicle, at which time I'll likely do 'the solution' if I can find someone able to do the work properly. Thanks for everyones input.

Quotes source post: 14520208

And in all but two cases the failures were from engines that had an OEM bearing fail, or that should have failed a pre- qualification procedure. No, as these engines age, we find that time in service, and corrosive wear matter MUCH more than mileage. This is why low mile cars fail at a greater rate than those that are driven, and even abused. This comes from direct experience, and the insertions made to our failure logs. NOTHING mechanical is eternal. I have documented 29 modes of failure for these engines, the IMS bearing is ONE of those. If the car has less than 50K miles in all these years of service, its at a much greater risk of failure than if it had well over 100K. You'll read all sorts of reports about this, hardly any of those are written by someone who has seen the failures, and dealt with them. They are opinionated people who want to be heros telling you what to do. This is the problem with the internet, youtube videos, and "articles". Three IMSB failure reports this week. One at 39K, one at 44K, and another at 27K miles. Thats a fact. Of those 3, two of the owners had no idea that the IMSB had a failure mode, and the other person thought that it was "hype"... He just bought the car 3 weeks ago, and he's learning the hard way. In fact, his previous comments pissed me off enough that I sent him packing when he wanted to buy my engine after the "hype" became true for him. I get so sick of people, their unsubstantiated opinions, and being typical ********. Anyway, rant off.

Quotes source post: 14520188

Super handy information for those of us who plunked down the cash for a dual-row retrofit back in 2012 when the IMS bearing alarm bells were ringing all over town. Of course, "don't do anything yet, the thing you REALLY want to buy will be available next year" doesn't sell many dual-row bearings.

Quotes source post: 14520379

It took 5 years for me to be convinced to allow the IMS Solution to be offered to the general public.The ONLY reason this occurred was because of a couple of clowns that decided to stop being LN customers, and start making a knock- off bearing kit. That pissed me off, so I decided to let LN execute an *** spanking to them. Thats when the Solution was revealed. Nothing else mattered, and still doesn't.

Hi Jake, Thanks for responding. I defer to your knowledge of this. However your reply has once again muddied the water and confused the situation for me. So I have a 2002 996 which received a LN IMS classic retrofit in 2013 from a shop that LN recommended and qualified my engine for (I got the green light). Now its 4.5 yrs later, I have about 10k miles on the bearing (and 60k miles on the car). You are saying simultaneously I am at risk because it is low miles and the bearing is 4.5 yrs old, but also there are essentially no failures from your bearings and many many other ways my engine could fail. So if there are (almost) no failures why would I do anything at this time? 4.5 yrs old seems like it is not very old for a bearing. My original OEM bearing was perfect after 11 yrs when it was replaced in 2013. The risk seems extremely small at this time. The 'keep the car forever' comment implies its eternal -- which you accurately say no mechanical thing is. So there has to be a practical/economic balance to this. This is all risk mitigation. It seems to me that if what you are saying is accurate (almost no failures from your bearings) then your advice should be that the risk of IMS failure is extremely small after retrofit, and investing further in 'the solution' is probably unnecessary unless money is no object or your engine is already torn down and the additional cost to installing it is minimal. Mike

Quotes source post: 14520444

I should have just kept my mouth shut, kept reading, and doing what I was doing. Which has a 5 year/ 50K mile service interval. It doesn't matter the mileage on the car- you are within 6 months of the recommended service interval from the bearing manufacturer. A lot like components used in the aviation world, "high time" components are considered, no matter the actual hours on them. This is especially true with the IMSB, as corrosive wear is a concern. Sorry that I didn't tell you what you wanted to hear. The recommended service intervals have a time in service, and mileage service interval for good reasons. If you choose not to follow this, for whatever reason, thats your decision. The IMS Solution can be reused at rebuild time. It has no contact components, no bearing cage, and the IMS is supported by a film of pressurized oil. De to this the component can be reused over and over again. I have one Solution that has been fitted to 11 different test engines, and is more than a decade old. It is so old that it was hand machined on equipment that was used to build B25s in WWII. Its not "my" bearing kit. I developed it, I use it in every engine I build, but I am well out of the chain of sales, and marketing. I benefit nothing from your bearing choice or purchase. In fact I ONLY benefit if someone's engine fails, and they have to come my way for a reconstruction. I have no role in parts sales. Again, all I can tell you is the bearing manufacturer has set forth the service interval recommendations. You can choose to follow those guidelines, or not. These recommendations are not new, and were stated in 2007, at the onset of the IMS retrofit era. Everyone seems to have forgotten that, and honestly most installers didn't bother reading it, or conveying it.

Not trying to frustrate you Jake. I understand the recommendations, and they are to mitigate the risk to LN engineering because all mechanical things fail eventually. What I'm trying to sort out is the reality of the situation. If the reality is that in a good engine (like mine was determined to be prequalifying for a retrofit), with a relatively new ceramic bearing AND there are essentially no reported failings of these bearings, then do I really need to do anything now. Put another way. Lets say when Porsche produced this car originally they had used LN ceramic classic retrofit bearings would this IMS ever have became a major problem - and would there have ever been a reason to develop 'the solution'. Would these cars have developed an 8-10% IMS failure rate... Thoughts?? Its probably an impossible discussion to have I realize now.

The recommendations have ZERO to do with mitigating losses. With th this pre-determined mindset in place, nothing I'll tell you will be comprehended in the manner that it should be. Raby- Out.

All recommendations have to do with mitigation of liability -- in fact that is the whole point of them. If you choose not to follow the recommendations then the responsibility lies on you and not the party that makes the recommendations. Sometimes ignoring recommendations is reasonable, if the cost or risk of following the recommendation is substantial or if the actual benefit of the recommendation is very small. That is what I'm trying to determine here. In fact I have a very open mindset about this -- I deal with risk mitigation and recommendations for very complicated situations on a daily basis. Its an interesting discussion to have, and certainly becomes relevant as these cars increase in age and likely decrease in value.

Quotes source post: 14519856

I love this analysis! and yes I think its relevant, my feeling is if you car has very low miles so there is a big question on other IMS failure factors like IMS runout etc then go for 'the solution'. If your car has lots of miles and X number of things could explode at any time, why spend the extra $900 or whatever to get from a ceramic bearing to the solution? the money saved can go on other factors that will have more value. In your analogy Gary or someone else, gets to spend that money saved on a new pair of ***** for his wife and lives happily ever after. Be smart like Gary, spend the extra on *****.

Somebody needs to get in their car and go for a drive! Wowiie Zowie!

Is this the point in the thread where we get ****** pics

I now have a headache

Quotes source post: 14520636

im not completely sure I understand what your saying, but I'm going with you on this. *****. Yes.

Quotes source post: 14521193

I don't want to see a set of $900.00 *****...Playdoh does not bounce back!

Added to the cost is the value one places on dealing with an m96 asplosion. How much insurance would you pay to eliminate risk of having to dispose of a roller, have it sitting around your property for the interim, not having a canyon car for half a season, having to do baseline maintenance on the next vehicle, risk of buying another Carrera with a serious pre-existing condition, etc. Then there's the issue that buying a Carrera in the first place isn't exactly grounded in logic. It's not a situation that lends itself to a single point, dollarized calculation.

The math doesn't even take into account that there is a residual (roller) value of 5-10k even if your engine does explode, and the option to outfit it with a newer (and possibly more bullet proof) engine if it does. Again you might have a 'solution' in your engine protecting your IMS but the rest of it is is still 15-20 yrs old and prone to multiple reasons to die. A new engine is probably ultimately what all 996s that stay on the road long term will end up with. It seems pretty clear to me that for the current value of these cars it is worthwhile to invest 1-3k on your IMS bearing if your going from 8%-10% risk (original bearing) to a retrofit bearing or solution. But it also seems pretty clear that economically at least its a bad decision to try and go from a 1% risk (an existing retrofit) to 0% (solution) unless your already in the middle of a substantial engine repair expense or your doing it DIY. The only nagging question to me is if the retrofit bearings will provide a longer term solution if the 4 yr/50K mile service recommendation is ignored. Will they eventually end up with an 8-10% failure rate in the next 5 years. Time will tell. If it does, we were warned.

Quotes source posts: 14522035, 14522582

Your in my head, dude. I spent months researching/reading online and now with more frequency after purchasing a 996. Result? Every time i get out of it, i say to myself, "well, it didn't explode!" And your comment cracks me up given that in my case, if it it does asplode, I still have a "canyon car" (my e30) and if it doesn't asplode, I still have a roller sitting in my driveway (my e30 parts car), so I'm good either way! Seriously though, there is no logic or rationale for buying a 911. For me, it's a passion thing. For others, a status thing. So to try infer prudent financial strategies isn't really possible. Spend what you want, spend what you can and hope for the best. This all rings true to me. Unless I've missed something, you can't sell off body parts after you die, and even if you can, you can't spend the money... cause ya dead. But there is life after death for Porsche, at least financially speaking. Or you can "bring it back to life." While those points don't exactly contradict the good Dr.'s analogy, it does impact it. You also bring to light something most relevant to me and my sitch as a new owner of a 14 year-old C4s with just under 100k on it's original IMSB: no matter how much money i spend with LN, there are a myriad of other ways for this car to die. Given i plan to replace the clutch/RMS/IMSB very soon after purchase, I have no plan to go with the solution. I'm going to take that extra $1k and put into other forms of PM and if in 4-5 years, this car is still running and makes me smile everytime i get in it.... I'll do what i need to for the next 5-10 years.

Sorry, posted to the wrong thread.